The invention relates to a method of and plants for recovering the sensible heat of slabs cast by the continuous casting method, wherein the slabs, after having been sheared to length, are guided through a cooling chamber within which heat is given off by the slabs to a cooling medium.
Since the rolling of continuously cast slabs into plates takes place discontinuously, it is necessary to store the continuously cast slabs in an intermediate storage room. In this intermediate storage room the slabs cool down to ambient temperature.
In order to utilize the sensible heat of the slabs, it is known to guide the slabs through a cooling chamber before their intermediate storage, within which chamber boiler pipes are arranged, through which a cooling medium, such as water, flows. This cooling medium is heated in the boiler pipes by heat radiated from the slabs. The steam that forms serves for the self-supply of heat for the steel making plant. With this known method the heat is supplied from the slabs to the cooling medium via the boiler pipes by radiation alone.
Since heat transmission by radiation is only efficient in the upper temperature regions of the slabs, i.e. between 900.degree. and 600.degree. C., the slabs that emerge from the cooling chamber, with this known method, have a temperature of more than 400.degree. C. If it were desired to lower the exit temperature of the slabs to below 400.degree. C., it would be necessary to increase the dwell time of the slabs within the cooling chamber by a multiple. Since the slabs are produced continuously, it would be necessary to either arrange several cooling chambers parallelly adjacent one another or to provide one cooling chamber of an extreme length. A low slab exit-temperature of below 400.degree. C., in particular of 150.degree. to 200.degree. C., not only is important because of the greater heat yield, but is also essential in order to allow the intermediate storage room to be designed as small as possible--the slabs can be piled more closely together when they have lower temperatures--and in order to achieve the shortest intermediate storage times.